A very light ideal spring with a spring constant (force constant) of 2.5N/cm pulls horizontally on an 18-kg box that is resting on a horizontal floor. The coefficient of static friction between the box and the floor is 0.65, and the coefficient of kinetic friction is 0.45. How long is the spring just as the box is ready to move? If the spring pulls the box along with a constant forward velocity of 1.75m/s, how long is the spring? how long is the spring if it pulls the box forward at a constant 2.75m/s?

Answers

Answer 1

(a) The length of the spring just as the box is ready to move is 5.1cm

(b) The length of the spring when it is pulled forward at a constant velocity of 1.75 m/s is 47.0 cm

(c) The length of the spring when it is pulled forward at a constant velocity of 2.75 m/s is 73.8 cm

What is the length of the spring just as the box is ready to move?

The length of the spring just as the box is ready to move is calculated by applying the principle of conservation of energy.

work done by static friction = elastic potential energy of the spring

μmgx = ¹/₂kx²2

μmg = kx

x = 2μmg/k

where;

k is spring constant  = 2.5 N/cm x 100 cm/m = 250 N/mμ is coefficient of static friction

g is the acceleration due to gravity

x is an extension of the spring

x = 2μmg/kx = (2 x 0.65 x 18 x 9.8) / 250x

= 0.051 m

x = 5.1 cm.

The length of the spring when it is pulled forward at a constant velocity of 1.75 m/s.elastic potential energy of spring  = kinetic energy of the box

¹/₂kx² = ¹/₂mv² kx² = mv² x²

= mv²/kx

= √(mv²/k)

where;

m is the mass of the box

v is the speed of the box

x is the length of the spring

x = √(18 x 1.75²/250)x = 0.470 mx = 47.0 cm

The length of the spring when it is pulled forward at a constant velocity of 2.75 m/s.x = √(mv²/k)x = √(18 x 2.75²/250)

x = 0.738 m

x = 73.8 cm

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Related Questions

A football is kicked by a place kicker. The average force on the
ball is 240 N and the impact lasts for a time interval of 0.25s.
Calculate the change in the ball's momentum.

Answers

The change in momentum of the ball that is kicked by a force of 240 N over a time interval of 0.25 s is 60 Ns.

What is change in momentum?

Change in momentum can be defined as the product of force and time.

To calculate the change in momentum of the ball, we use the formula below.

Formula:

ΔM = Ft.............. Equation 1

Where:

ΔM = Change in momentumF = Forcet = Time

From the question,

Given:

F = 240 Nt = 0.25 s

Substitute these values into equation 1

ΔM = 240×0.25ΔM = 60 Ns

Henece, the change in momentum of the ball is 60 Ns.

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Shandra is studying Earth's magnetic field in her science class. She leams that a giant shield around her planet protects all living things from dangerous charged particles from the sun.
How does the magnetic field protect life on Earth?

O A. The magnetic field directs charged particles toward the poles and then past Earth.
O B. The magnetic field directs charged particles toward the equator and then past Earth.
O C. The magnetic field absorbs the charged particles coming from the sun.
O D. The magnetic field directs charged particles toward the poles then absorbs them.

Answers

The magnetic field protect life on Earth by directing the charged particles toward the poles and then past Earth.

The giant shield around Earth that protects all living things from dangerous charged particles from the sun is called as Earth's magnetosphere. It is generated by the motion of molten iron in Earth's core. It also provides the basis for navigation using a compass.

The magnetosphere shields the life on Earth from the constant bombardment by charged particles emitted from the sun which is called as solar wind.

Therefore, the magnetic field protects life on Earth by directing the charged particles toward the poles and then past Earth.

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Which quantities (initial horizontal speed, initial vertical speed, range, flight time, or maximum height) are proportional to the square of the initial velocity?

(This is about angled projectiles)
(Include an explanation please)

Answers

Range and Maximum height are proportional to the square of the initial velocity.

In projectile motion, Range of the particle is the horizontal distance travelled by the projectile between launch and the landing points and is denoted as R,

R = u^2sin2θ/g

Here u is initial velocity.

Maximum height is the maximum height from the point of projection, a projectile can reach.

And at maximum height (h) attained, velocity of the object is zero (v=0)

we can use , v^2 - (u sinθ)^2= 2ah     (acceleration due to gravity is a= -g)

Or 0 -  (u sinθ)^2 = 2(-g)h

⇒ h = u^2 sin^2 θ / 2g

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Calculate the combined mass of the two people if the tension of the cable is 1205.4 N

Answers

Answer:

Let

T

be the tension of the cable and m

g

be the force of gravity. If the upward direction is positive, then Newton’s second law is T−mg=ma, where a is the acceleration. Thus, the tension is T=m(g+a). We use constant acceleration kinematics (Table 2-1) to find the acceleration (where v=0 is the final velocity, v

0

=−12m/s is the initial velocity, and y=−42m is the coordinate at the stopping point). Consequently, v

2

=v

0

2

+2ay leads to

a=−

2y

v

0

2

=−

2(−42m)

−12m/s

=1.71m/s

2

We now return to calculate the tension:

T=m(g+a)

=(1600kg)(9.8m/s

2

+171m/s

2

)

=1.8×10

4

N

Answer:

Explanation:

Given:

P = 1205.4 N

g = 9.8 m/s²

___________

m - ?

m = P / g

m = 1205.4 / 9.8 ≈ 123 kg

What do we call the number of waves that pass by a given point in one
second?
OA. The wavelength
OB. The frequency
о C. The amplitude
о D. The period

Answers

B: the frequency of the wave.



A__is the best example or representation of a concept.

Answers

A prototype is the best example or representation of a concept, which is used as a design to shape a device.

What is a prototype?

A prototype can be defined as a given design in its experimental stage which is very useful to shape the framework or idea to carry out.

Therefore, with this data, we can see that a prototype can be very useful to shape an idea or concept about a given device in particular.

Complete question:

Fill in the blank. A _____ is the best example or representation of a concept.

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1. A student tests the second law of motion by accelerating a block of ice at a rate of 3 m/s².
If the ice has a mass of 12.6 kg, what is the force must the student apply to the ice?

Answers

Answer: 37.8 N

Explanation:

F = ma (Newton's 2nd Law)

Force = mass x acceleration

F = (12.6 kg)(3 m/s2) = 37.8 N

Which of the following is accurate when discussing specific heat?
A) Specific heat values for solids will never vary for different ranges of temperature.
B) The specific heat of a gas can be measured at constant pressure.
C) Specific heat values for liquids will never vary for different ranges of temperature. D) The specific heat of a gas can be measured at constant volume only.

Answers

The statement indicating that the specific heat of a gas can be measured at constant pressure is accurate when discussing specific heat (Option B).

What is the specific heat of a gas?

The specific heat of a gas is a measurement that makes reference to the relative molecular position of the molecules in a substance in the gas state, which is a state of matter where particles are more separated in space when compared with liquid and solid states.

Moreover, specific heat can be defined as the amount of heat energy that may be able to increase the temperature of 1 gr (gram) of a given material to 1 Celssius degree.

Therefore, with this data, we can see that the specific heat of a gas depends on the temperature and it expresses a given amount of heat energy in a substance or material.

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I need assistance with these questions asap.

Answers

Answer:

Explanation:

9a)  Velocity North

30 m/s  * Sine(60) = 25.98076..  m/s

9b) Distance North

25.98076 m/s * (3 hour)  but we need hours in seconds b/c that's our velocity units

25.98076 m/s * 10800 s = 280,592.23 m

9c) Velocity East

30 m/s * Cosine(60) = 15 m/s

9d) Distance East

15 m/s * (3 hours)

15 m/s * 10800 s = 162,000 m

9e) Total displacement ( total distance  also known as  magnitude)

Total Distance = [tex]\sqrt{(Distant North)^{2} + (Distant East)^{2} }[/tex]

TD = [tex]\sqrt{280592.23^{2} + 162000^{2} }[/tex]

TD = 323999.99 m

let's round it to  324,000 m

324 Km

A car is traveling at 18.25 meters per second for 5.27 seconds. How far did it travel in meters? Round your answer to two decimal places. A car is traveling at 18.25 meters per second for 5.27 seconds. How far did it travel in meters? Round your answer to two decimal places.

Answers

96.18 meters

(96.1776 rounded to two decimal places is 96.18)

A man with a weight of 740N is standing on one leg. His foot is exerting 2312.5 N/m2 of pressure onto the ground. What is the surface area of the bottom of his foot?

Answers

Answer:

he surface area of the bottom of his foot is 3.2 m2.

Explanation:

A grandfather clock is operated by a slowly falling mass attached to a pulley system. Winding the clock lifts the mass up again. A typical grandfather clock has a 0.750 kg mass that can fall and be lifted a height of 1.80 m. Calculate the increase in gravitational potential energy of the mass when the clock is wound.​

Answers

13.23 joule is gravitational potential energy of the mass when the clock is wound.​

potential energy, p = mgh

m= 0.750 kg

h= 1.80 m

g=9.8 m/s²

p = mgh

p=0.750×1.80 m×9.8 m/s²

p=13.23 joule

Potential energy is a form of stored energy that is dependent on the relationship between different system components. When a spring is squeezed or extended, its potential energy increases. If a steel ball is lifted above the ground as opposed to falling to the ground, it has higher potential energy. It is capable of performing more work when raised. Potential energy is a characteristic of systems rather than of particular bodies or particles; for instance, the system made up of Earth and the elevated ball has greater potential energy as they get further apart.

Potential energy develops in systems having components whose configurations, or relative positions, determine the amount of the forces they apply to one another.

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In a crash, when a head hits an airbag, what is observed when the head first touches the
airbag and when the head stops? (keywords: speed, time, force)

Answers

When a head collides with an airbag in a collision, the head's initial velocity and its final velocity are measured.

What is the definition of force?

In economics, a power is defined as the pull or draw that modifies an object's velocity. Ingredients that might affect a person's sense of personal work or sleepiness are invisible to the human eye. Its dimensions and form are distinctive.

What does force mean in Example?

In daily life, there are many instances of forces, including: weight and force (i.e. the weight of something) the pressure a bat puts on a ball. the amount of force used to brush hair using a brush. the force used by your foot to press the pedal.

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A basketball spins on a player’s finger. The basketball starts with an initial rotational speed of 15 rad/s and stops spinning in 7.2 seconds. Find the angular displacement of the ball as it comes to a stop.

Answers

Answer:

Angular displacement  ≈  54 rad

Explanation:

Given:

φ₀ = 0

ω₀ = 15 rad/s

ω = 0

t = 7.2 s

___________

φ - ?

Rotational motion equation:

φ = φ₀ + ω₀·t + ε·t² / 2

Angular acceleration:

ε = (ω - ω₀) / t = ( 0 - 15 ) / 7.2 ≈ - 2.08 rad/s²

Angular displacement :

φ = φ₀ + ω₀·t + ε·t² / 2 = 0 + 15·7.2+ (-2.08)·7.2² / 2 ≈  54 rad

Two 1kg masses as distance D as part each exerted a gravitational attraction Force on the other one. If 1kg is now add to each mass the gravitational attraction exerted by each would be​

Answers

Answer:

Explanation:

m₁ = m₂ = m

m₁' = 2m₁ = 2m

m₂' = 2m₂ = 2m

F₁₂ = G·m₁·m₂ / D² = G·m² / D²

F'₁₂ = G·m'₁·m'₂ / D² = G·2m·2m / D² = 4·G·m²/ D = 4·F₁₂

Gravitational pull increased 4 times

What are the smaller bulbs called?

Answers

Answer:

E10 Miniature Edison Screw (MES) Also called “Miniature Screw

The smaller light bulbs are the E5 Lilliput Edison Screw (LES).

What are the common light bulb base sizes ?

Today, there are many applications that make substantial use of light bulbs. Lighting bulb bases come in a wide variety.

Based on the letter-number references, you can tell what size light bulb base it is. In contrast to the number, which designates the base's breadth, the first letter indicates the base's shape or form.

Following are the most typical diameters for light bulb bases:

Standard-Medium, normal sized screw in base: E26 or E27

Candelabra, a smaller screw in base: E12

Intermediate: E17

Bi-pin, having pin-in base including two points of contact: G4 or GU24

Twist-And-Lock base: GU10

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Explain clearly about hydrogeological Map​

Answers

Hydrogeological maps bring basic geological information together with data on the hydraulic and hydrochemical characteristics of the rocks and their usefulness for groundwater supply.

A girl rides her bicycle 1.40 kilometers west, 0.70 kilometer south, and 0.30 kilometer east in 12 minutes. The vector diagram below represents the girl's fist two displacements in sequence
from point P. The scale used in the diagram is 1.0 centimeter = 0.20 kilometer.

8. Determine the measure of the angle, in degrees, between the resultant and the 1.40-
kilometer displacement vector.

Answers

Answer:

See below

Explanation:

For a right triangle, remember that tan = opposite leg / adjacent leg:

The angle will be found by using the inverse tangent function

arctan ( .3/1.4)  = 12°

The measure of the angle, in degrees, between the resultant and the 1.40-kilometer displacement vector is 12.

What is vector?

In physics, a vector is a quantity with both magnitude and direction. It is often represented by an arrow whose length is proportional to the magnitude of the quantity and whose direction is the same as that of the quantity.

A vector does not have position, while having magnitude and direction. In other words, a vector's shape is unaltered if it is shifted parallel to itself as long as its length is unaltered.

Ordinary quantities with a magnitude but no direction are referred to as scalars in contrast to vectors. For instance, while speed (the amount of velocity), time, and mass are scalars, displacement, velocity, and acceleration are vector quantities.

Therefore, The measure of the angle, in degrees, between the resultant and the 1.40-kilometer displacement vector is 12.

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how would the shape of electric field lines change if you increased the voltage across the electrodes

Answers

Answer:

Explanation:

If the electric field is inhomogeneous, then the magnitude of the strength (and voltage) is determined by the density of the field lines: where the field lines are thicker, the field strength is greater

A block with mass 0.100 kg is moving to the left with velocity of -2.3 m/s on a frictionless surface. This mass proceeds to then slide into a spring, with spring constant of 1700 N/m

1. Draw a force diagram while the mass is interacting with the spring
2. What is the maximum compression of the spring (in cm)?
3. What is the velocity of the mass after bouncing off the spring

Answers

0.0135 cm distance  is the maximum compression of the spring.

mass=0.1 kg

velocity=2.3 m/s = 230 cm/s

spring constant, k= 1700 N/m

F=Kx

x=F/k

x=ma/k

x=0.1×230÷ 1700

x= 0.0135 cm

Distance is the length between two locations or things, independent of direction. Since distance is a scalar property, it only takes into consideration the total magnitude and ignores the start and finish positions. Since distance is a scalar attribute, it can only have a positive or zero value; it cannot have a negative value.

The most common unit of measurement for distance is the meter (m), while larger distances can also be stated in kilometers (km), while smaller distances can be expressed in centimeters (cm) or millimeters (mm). When calculating distance, the letter D is often used to represent the distance traveled.

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A 0.80 m wide door turns though an angle of 45°. How long is the arc of the displacement?
O 1.0 m
O 0.80 m
O 0.63 m
O 0.45 m

Answers

Answer:

below

Explanation:

If it went for 360° it would swing through the ENTIRE circumference = 2 pi r

     = 2 pi ( .8 ) =5.026 m

 but it only swings through 45   of the 360

      45 / 360    *  5.026 = .63 m


An airplane on a runway accelerates at 4.0 meters/second^2 for 28.0 seconds before takeoff. How far does the plane travel on the runway before
takeoff?

Answers

Answer:1568 meters

Explanation:

we will make a speed time graph and we will calculate the speed by multiplying acceleration with time and we will have the speed then we will draw it on the speed time graph this will make a triangle and we will calculate its area and we will have the distance.

A body moving with uniformly acceleration A has two point (5,15) and ( 20,60) on the velocity time graph of its motion. Calculate A. Pls I would like if the graph can be drawn I have the workings

Answers

Answer:

3 m/s

Explanation:

The slope of a velocity-time graph will give the acceleration for the object over the given interval.

Finding the slope:

[tex]a = \frac{y_2 - y_1}{x_2 - x_1} = \frac{60 - 15}{20 - 5} = \frac{45}{15} = 3\\[/tex]

The acceleration A would be 3 m/s

A 1.0 kg block is pushed 3.0 m at a constant
velocity up a vertical wall by a constant force
applied at an angle of 28.0
◦ with the horizontal, as shown in the figure.
The acceleration of gravity is 9.81 m/s2
.If the coefficient of kinetic friction between
the block and the wall is 0.30, find
a) the work done by the force on the block.
Answer in units of J.
b) the work done by gravity on the block.
Answer in units of J.
c) the magnitude of the normal force between
the block and the wall.
Answer in units of N.

Answers

(a) The work done by the force on the block is 9.99 J.

(b) The work done by gravity on the block is 29.4 J.

(c) The magnitude of the normal force between the block and the wall is 9.8 N.

What is the work done by the applied force on the block?

The work done by the applied force on the block is calculated as follows;

W = Fd cosθ

where;

θ is the angle of inclination of the applied forced is the displacement of the blockF is the applied force

F - μmg = ma

since the block is moving as constant velocity, acceleration = 0

Fcosθ - μmg = 0

F = μmg/cosθ

W = μmgd/cosθ

W = 0.3 x 1 x 9.8 x 3 / cos(28)

W = 9.99 (J)

The work done by gravity on the block is calculated as follows;

W = mg d cosθ

where;

m is mass of the block

W = 1 x 9.8 x 3 x cos(0)

W = 29.4 J

The magnitude of the normal force between the block and the wall is calculated as;

Fn = mg

Fn = 1 x 9.8

Fn = 9.8 N

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look at the two models of charges

Answers

Answer: im looking

explination

what is solenoid? define solenoid in simple words​

Answers

[tex]{ \red{ \underline{ \green{ \sf{solenoid}}}}}[/tex]

Solenoid is a coil of circular turns made up of insulated copper wire wrapped closely in the cylindrical form

solenoid is formed by circular turns of copper wire in cylinder form

URGENT!! ILL GIVE
BRAINLIEST!!!! AND 100 POINTS!!!!!

Answers

Answer:

1. B (graph A) 2. A (graph D) 3. D (graph B) 4. C (graph C)

Explanation:

1. Graph A gives the relationship between the speed of a car and time. Over time, the speed of the car is decreasing (moving closer to 0). Therefore, the car is slowing down.

2. Graph D gives the relationship between the distance of a car and time. Over time, the distance the car has traveled is increasing at a steady rate. Because the distance is changing, we know the car is moving. And because the slope of the line is constant, the car is moving at a constant speed.

3. Graph B gives the relationship between the distance of a car and time. This distance is not changing over time, meaning that if the car started 5 meters away, the car is still 5 meters away. Therefore, the car is not moving.

4. Graph C gives the relationship between speed and time. The speed is increasing, and therefore not constant. This means that the car is either speeding up or slowing down. Since speed is increasing (the inverse of graph A), we know the car is speeding up. When an object is speeding up, the velocity/speed and the acceleration have the same sign (both positive or negative). Our speed values are all positive, so our acceleration must also be positive.

need these answered with explanation please, i need this asap.

Answers

1. a. Frequency of the wave is equal to 2 cycles per second.

Wavelength of the wave is equal to 1.5 m.

2.a. The frequency of the wave is 3 cycles per second.

b, It is a longitudinal wave of wavelength is equal to 40 cm.

What is wave?

An energy disturbance in a medium without net particle mobility is referred to as a wave. Among the probable manifestations are elastic deformation, pressure changes, variations in electric or magnetic intensity, electric potential, and temperature changes.

From picture 1.

1. a. frequency  of the wave is = 2 cycles per second.

Wavelength of the wave is = 3 m/2 =1.5 m.

From picture 2.

2.a. As it moves forward and backward 3 times in very second, frequency of it is given by  3 cycles per second.

b, It is a longitudinal wave of wavelength is 40 cm.

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A motorcyclist heading east accelerates after he passes a sign post at x=0m marking the city his acceleration is constant a= 4m/s2 at time=0 he is 5m east of the sign post and has a velocity of v=15 m/s where is the motorcyclist when his velocity is 25m/s

Answers

Answer:

55m east of the sign post

Explanation:

Use this equation

final velocity^2 = initial velocity^2+2(a)(x) x is displacement.

Substitute values:

25^2= 15^2+ 2(4)(x)

625=225+8x

x=50 m

REMEMBER TO ADD INITIAL DISPLACEMENT!!!! :D

Displacement (positive is east in this case)

=50 m+ 5m

=55m.

So the answer is the motorcyclist is 55m east of the sign post.

Radio waves and microwaves have what type of frequency and
wavelength?
A.low frequency & long wavelength
B.high frequency & short wavelength
C.medium frequency & long wavelength
D.High frequency & long wavelength

Answers

Radio waves and microwaves have A.)low frequency and long wavelength.

What type of frequency and wavelength do radio and microwaves have?

Microwaves are classified as radio waves, but they have higher frequencies than other radio waves. And so with higher frequencies, they also have more energy. That's is the reason, microwaves are useful for heating food in microwave ovens.

Microwaves have a long wavelength, but not as long as radio waves. The  atmosphere of earth is transparent to some wavelengths of microwave radiation. The longer wavelengths pass through the atmosphere of earth more easily than the shorter wavelength microwaves.

Radio waves have photons with the low energies and microwaves have more energy as compared to radio waves.

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rosa suggests a source of error: some of the energy from the heating coil is lost because the insulation of the container is not perfect. what type of error will this cause? that is, will the experimental values for specific heat be higher or lower than the actual values? explain your reasoning. An orange juice producer buys oranges from a large orange grove that has one variety of orange. The amount of juice squeezed from these oranges is approximately normally distributed, with a mean of 4.10 ounces and a standard deviation of 0.20 ounce. Suppose that you select a sample of 16 oranges.a. What is the probability that the sample mean amount of juice will be at least 4.03ounces?b. The probability is 74% that the sample mean amount of juice will be contained between what two values symmetrically distributed around the population mean?c. The probability is 78% that the sample mean amount of juice will be greater than what value? Arbitrary imprisonments have been, in all ages, the favorite and most formidable instruments of tyranny.This quotation is consistent with Alexander Hamiltons vigorous support of which of the following? since hurricane deaths in the united states are down due to improvements in providing advance warnings, why are economic damages up? What is the value of -9? A. 18 B. 9 C. 0 D. -9 Pls help will give 20 Points! Who stars with kimberley sustad in the 2020 christmas movie, christmas by starlight?. Two tream merge to form a river. One tream ha a width of 8. 2 m, depth of 3. 4 m,and current peed of 2. 3 m/. The other tream i 6. 8 m wide and 3. 2 m deep, and flow at2. 6 m/. If the river ha width 10. 5 m and peed 2. 9 m/, what i it depth? How is clothing and furniture made into a fabric ? Where is Moscow founded? Can someone please help with 28? Write a paragraph discussing the organs and substances involved in mechanical and chemical digestion. choose the option that includes all the nouns from this sentence.when the weather turns cooler, the color of the leaves changes.weather, color, leavesweather, cooler, changesweather, cooler, color PLEASE HELP Idris is consuming a lot of antioxidants in his diet. What does this MOST likely mean? He is overweight. He eats healthy foods, He has a binge-eating disorder. He has a low BMR. If you are tossing a six-sided die, what is the probability of getting either a 1 or a 2 on your first toss and a 1 or a 2 on your second toss?. The area of the right triangle shown is 24 square feet. Which equations can be used to find the lengths of the legs of the triangle? Select three options. 0.5(x)(x + 2) = 24 x(x + 2) = 24 x2 + 2x 24 = 0 x2 + 2x 48 = 0 x2 + (x + 2)2 = 100 allison has recently finished high school and is now attending college. after earning her bachelor's degree, she plans to continue to graduate school. in addition, allison is not seriously dating anyone and thinks marriage and parenthood are years away. allison is at which developmental stage? De q se trata el cuento hotel de almagro de Ricardo piglia What is the meaning of a 95% confidence interval for a population mean? why are aids drugs like combivir so expensive? Which terms best describe the class of questions that insel and young were addressing when they studied the effect of antidiuretic hormone on monogamous voles by experimentally increasing the number of receptors in the brain?.